21251

What are the signs that the oil separator needs changing

ramaraju

Usually the Audi dealers top up the fluids(Engine oil, washer fluids etc) for free. Try this and see if it still decreases rapidly which indicates a leak or faulty oil filter (Happened with me and got the filter replaced which fixed the issue)

Guan Guan

I remember my new 2018 A6 at around 18,000 miles, the oil warning level light up. Call the dealer, and they told me to add one liter oil.
I believe that at 10 maintenance, they did not fill the oil to full.
Then at 20k maintance, I ask the tech, and he told me that these newer engines burn oil at a little higher rate then old engines.
Fast forward, now at around 25k, I check the oil drop a to the middle, but can last until 30k maintenance.
So, as long as I do a 10k oil change, should be ok.

S4'ed

If you are referring to the oil separator/PCV unit (not the oil filter), if the oil separator fails on a 2.0T, then you will likely get a Lean mixture at idle DTC code, and/or you will blow-out the rear crankshaft seal, and leak oil onto the ground.
If the oil separator fails on a 3.0T, you can have the Lean DTC and/or you can have coolant leaking into your oil, or just leaking out of the engine.

The oil separator/PCV unit of the 2.0T should be preemptively replaced with a new one every 50,000 miles. Only replace it with a genuine VW/Audi part (made by Hengst), not some other cheaper brand of part. About $150 and 20 minutes to replace, easy.
The oil separator/PCV unit of the 3.0T is a major job to replace, as it sits under the supercharger, and some difficult to remove pipes.

MurrayA4

Question.Prior to more stringent emissions standards of the last 10 years or so did this collected oil simply get put into the exhaust stream ?

S4'ed

PCV systems have been used on engines since the late 1950s, sending blowby gases from the crankcase back into the intake, thereby burning the gasoline vapor components in the engine. Earlier engines used a "draft tube", which just blew the blowby gases out of a tube under the floorpan, which was angled to allow the moving road air to create a slight vacuum, helping to evacuate the gases.

greasykid

I have had dozens of cars in my lifetime including 11 Audi's & am not familiar with an "oil separator". What is it & what does it do?

gk1

Not Audi's, but gives a good explanation.

MurrayA4

Wow gk1 good info.I prefer that my oil stays in the crankcase, maybe I'm fussy .I have a high mileage 14Tdi 3.0L and 99% of the oil stays down there for 15k kms/10k mls.

apoelistas

I don't like the design.

The PCV housing should have been metallic so should have been the valve I.e. metallic replaceable (threaded)

Another failure prone part.

Haven't seen a metallic.PCV (custom made) with a metallic replaceable valve yet. The one I have seen is bundled with catch can.

And a joke
When it fails one should sing don't cry for me Argentina ....
Why?
Ask the RMS.